Material housed within containers may include hazardous materials. These materials may generate gasses or vapors that need to be vented from the container. One may wish to have knowledge of the composition, and other physical characteristics such as pressure, temperature and humidity, of the gasses or vapors so that decisions can be made with respect to the material of the container along with physical characteristics of the container, such as pressure, temperature and the like, so that decisions can be made that an over-pressure or temperature condition is eminent or is present. This is especially true if the gases or vapors are potentially harmful. Opening the container to check on the gasses or vapors may not be feasible.